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Hello and welcome.



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And this video, I'm going to talk to you about the solution to reverse engineering X2.



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So I've opened a store in Iraq and.



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Now are looking at the more use the blocks, this first block here, I-40 and Rice and I agree in some



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variables over this sun, in this variabilities G string and this whole thing we've already seen before.



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So.



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This one I was also renamed to restring and the purpose of this part of the longest history in the string



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and tie inside the global variable input stream, and then this part here is very.



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Most.



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Two strings into two registers, Jean Postering is moving the idea and this string here.



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He's moving to our site and then there's a check function, which I agree animes have to check, and



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the purpose of this is to.



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Compay.



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This district here with G string and then to see whether they are the same, but is not so straightforward



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before it checks June postering, he does some kind of transformation on the string.



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So if you enter this function, you will see what I mean.



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So here are the eyes in.



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I was up with this comment and I and stream, so the string is actually this.



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You might think this is a password, but it is not.



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So if you try this, you will fail.



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So let's go back to.



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So here, nothing is moved to our.



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And there's also an implicit.



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Are the simply string.



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So these parameters, no and posturing are the parameters to transform function, which is how Surinamese



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transform.



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And then here there's also a new variable are eliminating Baffour and Jibaro.



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I have analyzed and found the device is the result of the transformation.



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So this function, we perform some kind of transformation and is able to her.



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And then after that down here, you move Dubuffet to RSI and then you move the numbers trying to idei.



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And then here you set the number of mice for comparison and then you do a memory compare that means



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and this past year is going to compare your stream with your transform string.



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And then only if it's equal, then if we return the result in a hurry so he can go back here.



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The result will be in our X, so our ranks will determine whether you have to be successful or not.



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You will test with our X is one.



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You've already one, then it's not zero.



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That means he will go to success is zero.



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Then he will go to hear failure.



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So is how so many times over here he will now take he will bring up the plus exclamation and plus which



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we have seen before.



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And then after that he is going to take your input string.



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Again, he will persist in pushing into your print printf have been a key function and I will say this



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happening is so important in string inside here and input string.



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He's in the eye and he's going to take the idea and do some kind of modification to.



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And then you bring you bring it up.



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This one is it.



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So this is how it works.



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So the thing is, you have to analyze is how to how this to take your your input string and transform



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it.



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Right.



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So basically, I've already put a comment here to show you what one is, but this is basically taking



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your your input stream.



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And then do some kind of transformation, you conveniently have transformed, so for better understanding,



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easier understanding and going after to transform this industry, you compare to see that 80, 90 and



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so on.



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So now what remains to be done is to analyze how it's a transformation done, to understand that the



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FTA and then and then I saw this U.S. Navy SEAL moving yo yo, and I'm starting to job and I hear.



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It is putting your input between the RTI and Jibaro here, so he's going to take your input string,



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perform some kind of transformation in Ghaffur.



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So we have to enter this function to see how he does it.



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And here is why he's doing it.



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So over here, he's taking all your input string.



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And going in three, two times in a row now, each time you lose, you notice how labeled are 14 is



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high, meaning the count.



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So the country doesn't agree to you continue to look.



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So you looked at two times a year.



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I put a comment here to indicate three, two times.



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And here what he does is you call a function Jewish community federation function, and he will go in



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each time he goes in, he counts.



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It is a counter argument as a barometer.



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He also takes how the eye has to argue in the eye from here in blistering.



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OK, so listen to this and see how he does and then I analyze this, if you enter this loop and you



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will find it, what is actually doing is it is performing all this kind of operation inside here.



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I assume the idea is actually easier to follow the first thing that he has to fighting it and then it



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doesn't.



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An operation with one F one F means fine ones in binary, which is a musketry and is limiting the operation



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to fight bitterly.



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That's why he's doing the mosque then issue.



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Right.



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And she's right.



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This operation there must issue, right?



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And you all hear these stories actually are going down for it.



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So I you see there just happens three times once here and here and any time.



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And in hearing anything and then after a disservice to disability, right?



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Three times he would then have you assume that the result is starting X, which is why so now over here



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he would take the Y and then he will add to itself and is to Y, and here you had to be so against this



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three way.



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And finally he were performing a bit, masking using the N operator in here.



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So let me meeting you our operation to find her.



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So in effect what he is doing is rotating the beast to the right.



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Now, if you want to implement this insight, Python, and this is what it looks like, I've got the



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scoop here.



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So I open this in the terminal



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SkyPan Scritch.



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All right, so I'll explain this in the next video.



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Thank you for watching.